Can CBD Alleviate the Symptoms of Epilepsy?

There have been many examples in recent years of published scientific articles, which have been peer-reviewed, as well as news items in the more general press, which have indicated the broad range of medical conditions susceptible to treatment by cannabis and related compounds.

Much publicity has been gained in particular for reports claiming to demonstrate the beneficial effects of cannabis on childhood epilepsy, a most distressing disease. A widely read and reputable US Journal “Scientific American” has published an article describing and analyzing the current data on this subject, which has been gathered in the US state of Colorado. The overall but not surprising conclusion of the article is that more and better-managed trials are essential. Drug companies are already working on compounds related to cannabis that show the benefits without the associated cognitive problems, which are linked to the psychoactive compound THC. GW Pharmaceuticals has developed two marijuana-derived drugs, Epidiolex and Sativex, the latter already available as prescription items in some countries. Epidiolex, a purified form of cannabidiol [CBD], is intended to treat epileptic seizures and is being tested in an international clinical trial led by the University of California, San Francisco, Epilepsy Center. It has already been granted orphan drug status—a path to approval based on smaller clinical studies than normal—by the US Food and Drug Administration [FDA].

“…it affects approximately 50 million people with about 1% showing active symptoms.“

The reported case of Charlotte Figi, a child whose nearly constant seizures were dramatically curtailed with cannabidiol, has now led to more large scale trials being started using established protocols [placebos and double-binding] to provide an acceptable medical, as opposed to anecdotal, basis for the arising results. A brief explanation of the neurological condition known as epilepsy will provide a context for these developments.

Epilepsy is a chronic neurological disorder of the human brain and has been seen in almost all countries across the world with the best estimates indicating that it affects approximately 50 million people with about 1% showing active symptoms. According to the World Health Organisation [WHO] the disease is characterised by recurrent seizures, which are brief episodes of involuntary movement that may involve a part of the body (partial) or the entire body (generalised). Other symptoms, usually of short duration, occur including loss of awareness and sensation (including vision, hearing and taste) and the loss of other cognitive functions as well as mood changes.

“Although more data are needed, animal studies and clinical experience suggest that marijuana or its active constituents may have a place in the treatment of partial epilepsy.

[In the study] we present the case of a 45-year-old man with cerebral palsy and epilepsy who showed marked improvement with the use of marijuana. This case supports other anecdotal data suggesting that marijuana use may be a beneficial adjunctive treatment in some patients with epilepsy.”

Seizures are a result of excessive electrical discharges in a group of brain cells with the site of the discharge varying from person to person. The frequency of seizure events can vary from one per annum up to several per day. There has been much debate as to what constitutes epilepsy in terms of a clinical diagnosis but there is now general agreement among neurologists that epilepsy is defined as having 2 or more unprovoked seizures [this distinction became necessary when it was recognised that single seizure events might occur only once in a lifetime].

Misunderstanding of epilepsy is widespread with some popular beliefs concluding that epilepsy is contagious. This is not the case! Two types have been defined: idiopathic epilepsy, with no identifiable cause and is thus unavoidable, affecting 6 out of 10 people with the disorder; secondary epilepsy or symptomatic epilepsy with well-identified causes, which in principle could be avoided. Such causes include brain damage from prenatal or perinatal injuries (e.g. a loss of oxygen or trauma during birth); congenital abnormalities or genetic conditions with associated brain malformations; a severe head injury; a stroke that restricts the amount of oxygen to the brain; an infection of the brain such as meningitis, encephalitis, neurocysticercosis; certain genetic syndromes; a brain tumour.

WHO claims that epilepsy can be treated easily and affordably with daily medication costs as low as US $5 per year. Recent studies in both low- and middle-income countries have shown that up to 70% of children and adults with epilepsy can be successfully treated (with success being defined as complete control of seizures) with anti-epileptic drugs (AEDs). In contrast to drugs which have a curative effect anti-epileptic drugs are intended to prevent seizures from occurring. Some medications are taken as a ‘course of treatment’ for a disease or to cure a condition (for example, taking a course of antibiotics for an infection). Anti-epileptic drugs (AEDs) are different; they are a preventative medication taken every day to try and stop seizures from happening. They appear to do this by reducing the excessive electrical activity in the brain that causes seizures but the details of the mechanism are not well understood. The development of more than 20 compounds with anti-epileptic properties represents a major advance for sufferers.

The current interest in cannabis as an anti-epileptic agent is in part the result of claims that it has successfully been used to treat young children in the USA suffering from “Dravet’s Syndrome”, a debilitating condition characterised by constant seizures, often as many as several hundred per week. Treatment with a cannabidiol extract has been shown to reduce, in some instances, the number of seizures to less than 10 per week! The parents of children with this syndrome have been very vocal in their demands for the drug to be made available as soon as possible. Indeed some families have moved to Colorado to access the drug. The opposition has focussed on the lack of solid clinical trial data and is further compounded by the federal Schedule 1 drug classification, which effectively has blocked broad scientific research on cannabis. However, in late 2015, the United States Drug Enforcement Administration (DEA) eased some regulatory requirements imposed by the Controlled Substances Act (CSA) for those who are conducting FDA-approved clinical trials on cannabidiol (CBD). These changes may well improve the overall research process regarding CBD’s possible medicinal value and encourage ongoing scientific studies with a broad range of medical issues being addressed. The future is seemingly bright if the science is sound and politicians are supportive.